The present invention relates to a camera with an electronic flash, and more particularly to an electronic flash charging circuit incorporated in a camera equipped with electrically controlled elements as well as an electronic flash.
Compact cameras have been developed with improved automatic control functions, such as automatic focusing, automatic exposure, automatic film winding, effected by means of a microcomputer. When an electronic flash is built into such a compact camera, it is preferred to use a power source common to all of the electrically controlled elements in order to ensure that the compact camera does indeed remain compact in size.
Charging a capacitor of the electronic flash causes a potential drop. If the potential of the power source drops lower than a potential sufficient for the microcomputer to operate effectively, the microcomputer does not operate properly when the capacitor of the electronic flash is being charged, whereby the camera operation will come to a standstill.
To operate the microcomputer effectively with a potential lower than its effective operating potential, it has been proposed that a voltage compensating circuit be provided or that a back-up capacitor for noise elimination having a large capacity, be provided in order to back up or support the microcomputer. Such an incorporation of an electronic flash charging circuit including a large capacity back-up capacitor or a voltage compensating circuit is, however, apt to increase not only the size but also the cost of the camera.